Copulatory courtship in Drosophila: Behavior and songs of D. birchii and D. serrata

D. birchii and D. serrata, two endemic Australian Drosophila species, have a copulatory courtship. The males of these species begin to court the femal e after mounting her and often go on with the courtship after the copulatio n is over. In the present paper we have described behaviour interactions be tween the male and the female and analyzed acoustic signals produced by the flies during courtship. Species differences were move pronounced in female than in male behavior. Variation within the species was obvious in the rel ative proportions of lime the flies spent in different behaviors. Even thou gh courtship took place nearly solely during copulation, some remains of pr ecopulatory courtship were observed in both species. It is suggested that c opulatory courtship exhibited by D. birchii and D. serrata flies is a deriv ed rather than a primitive character.